Make more libraries available (#1917)

* Make more libraries available to plugin dvelopment

* Add Unzip function to util

internal/util/util.go

@@ -1,9 +1,11 @@
 package util
 
 import (
+	"archive/zip"
 	"bytes"
 	"errors"
 	"fmt"
+	"io"
 	"os"
 	"os/user"
 	"path/filepath"
@@ -435,3 +437,56 @@ func ParseSpecial(s string) string {
 func String(s []byte) string {
 	return string(s)
 }
+
+// Unzip unzips a file to given folder
+func Unzip(src, dest string) error {
+	r, err := zip.OpenReader(src)
+	if err != nil {
+		return err
+	}
+	defer r.Close()
+
+	os.MkdirAll(dest, 0755)
+
+	// Closure to address file descriptors issue with all the deferred .Close() methods
+	extractAndWriteFile := func(f *zip.File) error {
+		rc, err := f.Open()
+		if err != nil {
+			return err
+		}
+		defer rc.Close()
+
+		path := filepath.Join(dest, f.Name)
+
+		// Check for ZipSlip (Directory traversal)
+		if !strings.HasPrefix(path, filepath.Clean(dest)+string(os.PathSeparator)) {
+			return fmt.Errorf("illegal file path: %s", path)
+		}
+
+		if f.FileInfo().IsDir() {
+			os.MkdirAll(path, f.Mode())
+		} else {
+			os.MkdirAll(filepath.Dir(path), f.Mode())
+			f, err := os.OpenFile(path, os.O_WRONLY|os.O_CREATE|os.O_TRUNC, f.Mode())
+			if err != nil {
+				return err
+			}
+			defer f.Close()
+
+			_, err = io.Copy(f, rc)
+			if err != nil {
+				return err
+			}
+		}
+		return nil
+	}
+
+	for _, f := range r.File {
+		err := extractAndWriteFile(f)
+		if err != nil {
+			return err
+		}
+	}
+
+	return nil
+}